/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.catalina.users;

import javax.naming.Context;
import javax.naming.Name;
import javax.naming.RefAddr;
import javax.naming.Reference;
import javax.naming.spi.ObjectFactory;
import java.util.Hashtable;

/**
 * <p>JNDI object creation factory for <code>MemoryUserDatabase</code>
 * instances.  This makes it convenient to configure a user database
 * in the global JNDI resources associated with this Catalina instance,
 * and then link to that resource for web applications that administer
 * the contents of the user database.</p>
 * <p>
 * <p>The <code>MemoryUserDatabase</code> instance is configured based
 * on the following parameter values:</p>
 * <ul>
 * <li><strong>pathname</strong> - Absolute or relative (to the directory
 * path specified by the <code>catalina.base</code> system property)
 * pathname to the XML file from which our user information is loaded,
 * and to which it is stored.  [conf/tomcat-users.xml]</li>
 * </ul>
 *
 * @author Craig R. McClanahan
 * @since 4.1
 */
public class MemoryUserDatabaseFactory implements ObjectFactory {


	// --------------------------------------------------------- Public Methods

	/**
	 * <p>Create and return a new <code>MemoryUserDatabase</code> instance
	 * that has been configured according to the properties of the
	 * specified <code>Reference</code>.  If you instance can be created,
	 * return <code>null</code> instead.</p>
	 *
	 * @param obj         The possibly null object containing location or
	 *                    reference information that can be used in creating an object
	 * @param name        The name of this object relative to <code>nameCtx</code>
	 * @param nameCtx     The context relative to which the <code>name</code>
	 *                    parameter is specified, or <code>null</code> if <code>name</code>
	 *                    is relative to the default initial context
	 * @param environment The possibly null environment that is used in
	 *                    creating this object
	 */
	@Override
	public Object getObjectInstance(Object obj, Name name, Context nameCtx,
	                                Hashtable<?, ?> environment)
			throws Exception {

		// We only know how to deal with <code>javax.naming.Reference</code>s
		// that specify a class name of "org.apache.catalina.UserDatabase"
		if ((obj == null) || !(obj instanceof Reference)) {
			return (null);
		}
		Reference ref = (Reference) obj;
		if (!"org.apache.catalina.UserDatabase".equals(ref.getClassName())) {
			return (null);
		}

		// Create and configure a MemoryUserDatabase instance based on the
		// RefAddr values associated with this Reference
		MemoryUserDatabase database = new MemoryUserDatabase(name.toString());
		RefAddr ra = null;

		ra = ref.get("pathname");
		if (ra != null) {
			database.setPathname(ra.getContent().toString());
		}

		ra = ref.get("readonly");
		if (ra != null) {
			database.setReadonly(Boolean.parseBoolean(ra.getContent().toString()));
		}

		// Return the configured database instance
		database.open();
		// Don't try something we know won't work
		if (!database.getReadonly())
			database.save();
		return (database);

	}


}
